When Otto meets a dingbot (www.girlgeniusonline.com) then the result can only be a DingbOtto.
The secondary reason for designing this, other than I have a liking for small crazy robots, is to allow holding a bigger battery pack. My first Otto ran with no problem off an external power feed, even from a powerbank, but could not run off its internal 16340 battery. It would work with 2 servos attached, occasionally with 3, but never with 4. This holds a double 18650 battery shield. I will post a real photo rather than just renderings once I have finished painting the model. At the moment it is just a pile of PLA pieces.
Part designs are available at https://www.thingiverse.com/thing:4788924.

Here there is a video of the single booster using a small 16340 lithium cell from 3.7V to 5V to power a humanoid alike Otto with 6 mg90a servos at the same time in some movements (the metal ones) including a neopixel matrix 4x4 in full brightness.

I also tested the module separate and it powers more than 2 servos at same time Piers Kennedy Bill SCHONFELDER

Timm H. Try testing them out separate from the nano

Buenas. He realizado mi primer Otto Humanoide y estoy teniendo problemas con la alimentación. He utilizado el esquema estándar para su conexión. Siempre utilizo pilas AA nuevas pero cuando le doy alguna orden Otto se reinicia por falta de alimentación. ¿Hay alguien que haya construido un Otto Humanoide y le funcione correctamente con baterías AA y me pueda compartir su experiencia?
Gracias por vuestra ayuda.